Method and system for sender-controlled messaging and content sharing

ABSTRACT

A messaging and content sharing platform that allows for sender-controlled permissions and rules. During operation, a sending device can receive user input to set permissions and rules for an object to be sent to a receiving device. The permissions and rules control how the object will be managed after leaving the sending device. A receiving device receives the object and complies with the permissions and rules associated with the object. Other features of the platform include a hierarchical view for group messaging, an attachment-only view of messages, large file attachments, and the ability to allow users to access external services such as social networking websites without logging in.

RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 62/183,855 Attorney Docket No. PRIV15-1001PSP, entitled “METHOD AND SYSTEM FOR CONTROLLING ACCESS TO ENCRYPTED DATA,” by inventors Shaun Murphy, Charles Murphy, and Richard Johnson, filed 24 Jun. 2015.

The subject matter of this application is related to the subject matter in a co-pending non-provisional application by the same inventors as the instant application and filed on 4 Jun. 2012 entitled “CONFIDENTIAL MESSAGE EXCHANGE USING BENIGN, CONTEXT-AWARE COVER MESSAGE GENERATION,” having application Ser. No. 13/488,391, Attorney Docket No. PRIV15-1001PSP, the disclosure of which is incorporated by reference herein.

The subject matter of this application is related to the subject matter in a co-pending non-provisional application by the same inventors as the instant application and filed on 30 May 2013 entitled “METHOD AND SYSTEM FOR AUTOMATIC GENERATION OF CONTEXT-AWARE COVER MESSAGE,” having application Ser. No. 13/906,039, Attorney Docket No. PRIV15-1001PSP, the disclosure of which is incorporated by reference herein.

BACKGROUND

Field

This disclosure is generally related to messaging and content sharing. More specifically, this disclosure is related to a messaging and content sharing platform with sender-controlled security and other features.

Related Art

As an increasing number of users come online, they discover the joys and pitfalls of communicating over the Internet. Users find that they like to share content and communicate with each other over Internet. However, as many users have realized too late, once their e-mail has been sent out they no longer have control how their e-mail is being used. Their e-mails and other communications can be forwarded to others and quickly spread beyond their intended audience. This can have a detrimental or even devastating effect on the original sender, who did not intend the reading audience to expand beyond the original recipient. Therefore, a better way for users to control their communications is needed.

SUMMARY

One embodiment provides a system for sending an object. During operation, a sending device receives the object, wherein the object is a message or other content. The sending device may receive user input to set permissions and/or rules for the object. A respective permission indicates a respective operation that a receiving device may perform on the object, and a respective rule indicates an operation that the receiving device performs when a specified condition occurs in connection with the object. The sending device may attach the permissions and rules to the object. The sending device then sends a portion of the object to the receiving device.

In some embodiments, the sending device may generate a unique identifier for a portion of the object. The sending device may then send the portion of the object with the unique identifier to a server. The unique identifier is optionally stored via a distributed lookup table including but not limited to a distributed hash table. The sending device may then send the unique identifier to the receiving device.

In some embodiments, in a messaging session involving a plurality of users, the sending device may display responses to each user according to a hierarchical structure so that a response to a message in a message thread is depicted as branching off from the message.

In some embodiments, a rule is one of: disallowing the receiving device from forwarding the message; disallowing the receiving device from taking a screenshot of the object; disallowing the receiving device from printing the object; disallowing the receiving device from downloading the object; requiring that the receiving device delete an object after taking a screenshot; and requiring that the receiving device delete an object after the user views the object.

In some embodiments, the sending device allows the user to anonymously send a message and/or other content to an external service. The sending device may verify the identity of the user, and allow the user to receive messages from others and continue messaging with others using the user's verified identity.

In some embodiments, the sending device displays a plurality of messages in attachment view so that the user may view only the attachments, in which an attachment includes a generated thumbnail for each file that is smaller than the original size of the file.

In some embodiments, a permission indicates whether the receiving device is allowed to perform one of the following: forward the message and/or content; stash the message and/or content; add a participant to a message header indicating parties that receive the message and associated replies; remove a participant from the message header indicating parties that receive the message and associated replies; take a screenshot that includes the message and/or content; select text from the message and/or content; print the message and/or content; and download the message and/or content to external storage.

In some embodiments, the object is encrypted with a symmetric key and the symmetric key is encrypted with a public key of the receiving device. Furthermore, sending the portion of the object further includes encrypting the object and sending a portion of the encrypted object to the receiving device.

In some embodiments, the sending device may receive user input to specify permissions for others to access and roll back an item in a stash.

In some embodiments, the sending device may perform optical character recognition on attachments. The sending device may then receive user input specifying a search item, and search through the attachments and associated metadata for the search item.

Another embodiment provides a system for receiving an object. During operation, a receiving device receives the object, wherein the object is a message or other content. The receiving device may extract permissions and/or rules from the object. A respective permission indicates a respective operation that the receiving device may perform on the object, and a respective rule indicates an operation that the receiving device performs when a specified condition occurs in connection with the object. The receiving device may then provide the object to a user.

In some embodiments, the object is encrypted, and decrypting the object involves obtaining an encrypted portion of the object from a server.

In some embodiments, the receiving device receives user input specifying an operation to be performed on the object. The receiving device may then determine whether the operation is authorized based on the rules and/or permissions of the object. Responsive to determining that the operation is authorized, the receiving device may perform the operation on the object.

In some embodiments, the object is encrypted and extracting permissions further includes: the receiving device decrypts and extracts a symmetric key from the message using a private key of the receiving device. The receiving device then decrypts the object with the symmetric key.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates an exemplary network environment that facilitates a messaging and content sharing platform with sender-controlled security in accordance with an embodiment.

FIG. 2 presents a flowchart illustrating a method for sending a message and/or content to a recipient in accordance with an embodiment.

FIG. 3 presents a flowchart illustrating a method for receiving a message and/or content in accordance with an embodiment.

FIG. 4 presents a flowchart illustrating a method for anonymously accessing an external service in accordance with an embodiment.

FIG. 5 presents an illustration of a screen that allows a user to set rules for a new message in accordance with an embodiment.

FIG. 6 presents an illustration of a screen that allows a user to change permissions on all recipients of a new message in accordance with an embodiment.

FIG. 7 presents an illustration of a screen that shows an exemplary hierarchical display of group messages in accordance with an embodiment.

FIG. 8 illustrates an exemplary computer system that facilitates a messaging and content sharing platform with sender-controlled security in accordance with an embodiment. In the figures, like reference numerals refer to the same figure elements.

DETAILED DESCRIPTION

The following description is presented to enable any person skilled in the art to make and use the embodiments, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. Thus, the present invention is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

Overview

Embodiments of the present invention solve the problem of providing sender-controlled messaging and content sharing security by allowing a user to set rules and permissions to control the use and lifecycle of messages and/or other content. A messaging and content sharing platform and system includes a client installed on each mobile device that allows a sender to set permissions and rules for a message or content. These permissions and rules give the sender complete control over how a receiving party may use the message and/or content. For example, a sender may disallow the receiving party from forwarding, taking a screenshot, printing, or downloading the message. The sender may also require that the receiving device delete the message after taking a screenshot or after the user views the message. Note that embodiments of the present invention are not limited to the disclosed examples.

The messaging and content sharing platform may also feature a hierarchical display for group messaging that utilizes a tree structure to illustrate the threads of a conversation when multiple users are communicating with each other. This allows the user to easily follow the group conversation and see who is messaging whom in the conversation.

The messaging and content sharing platform may also include an attachment-only view so that a user can scroll through the list of file attachments and filter attachments to find what they need. The attachment-only view may apply system-wide (e.g., in the inbox, contact view, and message view). The attachment-only view may be available anywhere a file may be associated with a system object or action. The system may allow for large file attachments (e.g., one terabyte or greater). Management of large file attachments is transparent to the user and users do not need to separately upload large files to another server themselves.

Some embodiments may also include a zero-login feature that allows a user to use an external service, such as a social networking service, without logging in. The user can use the social networking service anonymously to contact others until the user wants to authenticate his identity with the external service.

Exemplary Network Environment

FIG. 1 illustrates an exemplary network environment 100 that facilitates a messaging and content sharing platform with sender-controlled security in accordance with an embodiment. Network environment 100 can include a computer network 102, which can include any wired or wireless network that interfaces various computing devices to each other, such as a computer network implemented via one or more technologies (e.g., Bluetooth, Wi-Fi, cellular, Ethernet, fiber-optic, etc.). In some embodiments, network 102 includes the Internet.

Network environment 100 can also include a computing device 104, which a user 106 uses to communicate a message or content to another computing device, such as computing device 110 or computing device 112. User 114 operates computing device 110 and user 116 operates computing device 112. User 106 may use a messaging and content sharing client 118 installed on computing device 104 to send messages or other content to the other users. The message or content can be text, voice, and/or video. Client software 118 allows a user to send messages, message attachments, files, and other content. Computing device 110 and computing device 112 also have installed messaging and content sharing clients 120, 122 respectively. User 106 may also anonymously access external services, such as social networking service 123. Although FIG. 1 depicts computing device 104 as a smartphone, computing device 104 can be also be a personal computer or any device that user 106 can use to send messages or share file/content with user 112.

A messaging and content sharing server 124 can store and execute server software, and may store content such as files or attachments from messages that a user shares with others. The system may split up a file so that malicious attackers have greater difficulty finding and reassembling the separate parts of the encrypted file. Server 124 can store small portions of encrypted files and/or large portions of the encrypted files. The system may also send a large portion of an encrypted file to an enterprise hardware device, such as an enterprise server 126, for storage. Further, the system may store a large portion of the encrypted file using cloud storage services, such as cloud storage server 128. Note that generally the system can split apart objects (encrypted or not), and store a portion of the object in one location and the remainder of the object in any number of other locations, the details of which are further disclosed in U.S. Provisional Application No. 62/183,855. Objects may include, but are not limited to, pictures, videos, documents, text messages, emails, and other digital items.

Permissions and Rules

A user may control the use of messages or other content using permissions and rules. A permission associated with an object, such as a message and/or content, indicates an operation that a receiving device may perform on the object. The user may set one or more permissions to control the operations that the recipients can perform with the messages/content. For example, the user may set permissions to allow or prevent forwarding a message, locally download an attachment, and add/remove a participant in a group message. The user may also set permissions to allow or prevent taking a screenshot, printing, and/or archiving a message or content. The user can set default permissions that apply globally or per contact. The user can also set fine-grained permissions, such as permissions that apply per user and/or per attachment. Furthermore, the user may change the permissions at any time.

A rule associated with an object, such as a message and/or content, indicates an operation that the receiving device performs when a specified condition or event occurs. For example, a rule may specify that a receiving device delete a message and/or content after it has been read. Another rule may specify that a receiving device delete a message and/or content after a certain time period. Another example of a rule is that a receiving device is required to delete all messages and/or content sent to a user if the user tries to take a screenshot of the message and/or content. As another example, the user may set a rule to control the length of time that the message and/or content is available to recipients. The user may set default rules that apply globally or per new message and/or content sent, and the user may change the rules at any time.

Note that all objects in the system are associated with permissions and rules, and embodiments of the present invention are not limited to the example permissions and rules. When a device obtains or generates an object, the device can determine the permissions and rules associated with the object and perform operations on the object or manage the object in accordance with the object's permissions and rules. For example, message objects, stored content objects, and file attachment objects are all associated with permissions and rules and a device that obtains or generates an object will comply with the permissions and rules associated with the object. Moreover, the entire messaging and content sharing system complies with permissions and rules set for objects, and embodiments of the present invention are not limited to the example objects.

Besides permissions and rules, the user can also delete a message across all devices. The user can send a message and then pull back the message. If the recipient forwards a message the user can choose to delete across all devices, including any forwarded messages, to pull back the forwarded message. By pulling back the message from a receiving device, the receiving device no longer has access to the message. Furthermore, when a user forwards a message, the system can guarantee that the user has not modified the forwarded information in any way. The system may secure a message so that the user may not tamper with the message when forwarding the message to another user. A user can not manipulate or otherwise tamper with a message and then forward it to another user without others (e.g., the user receiving the forwarded message and/or the sending user) knowing of the changes.

Sending Large Files

The system may also allow for sending large file attachments, such as terabyte-size attachments, by combining cloud storage with messaging. Current messaging systems are generally designed for storing and sending text messages, not binary files/objects or very large files/objects. A user may send a large file through the messaging system without the user needing to upload the large file to a storage service that can handle large files. The system may divide a large encrypted file into a small portion that the system may send with the message and a large portion that the system sends to a remote server for storage and access by others.

The system may generate a link or reference to the large file or a significant portion of the large file and include the link with the message. The system may also generate a universal unique identifier for the large file. Generally, the system may assign a universal unique identifier to each object. The universal unique identifier is not tied to any specific user. This facilitates storing links to content via a distributed hash table so that the content is not stored on a central storage point.

The system may send the universal unique identifier and the link to the receiving device, and, in some embodiments, may also include a small portion of the large file with the message. The system may send the large file to a server with the universal unique identifier.

The server may store data associating the file attachment with the unique identifier. The system may include a distributed hash table implemented across multiple servers to store the associations between the unique identifier and stored data (e.g., the file attachment). A server may send the file attachment to any device that queries for data using the unique identifier. For example, when a device receives a message, the device obtains the unique identifier to retrieve the large file attachment. The user on the receiving device does not need to know that the large file attachment was retrieved from a remote server (e.g., a file storage service).

In some embodiments, the system may also provide an attachment-only view. When the user selects this view, the system hides the conversation portion and only displays attachments. The system may display multiple pictures of varying sizes that indicates to the user the contents of the attachments. The system may perform optical character recognition on the attachments to allow the user to search through the attachments. The user can scroll through a list of attachments to find what the user is searching for. The user can filter or sort the attachments in different ways, such as by date, filename, and/or sender name. The user may search through metadata in attachments and also use Boolean logic to combine different sorting and filtering conditions. For example, the user may specify to sort according to name and date. Further, each file/attachment may have a client-generated thumbnail for each file that is very small in size and quick to transfer. This thumbnail may be generated by a sending device. This provides the recipient a way to see a lower resolution preview of each picture, video (e.g., animated preview), Word document, etc. without having to download the original document. The attachment view features may also include the ability or intelligence to search for content inside and around the files (e.g., optical character recognition, meta data search, etc.) for advanced search and sorting. Note that current e-mail software requires the user to go through old e-mail messages to find attachments and this can be very inconvenient and slow for a user since the user must click each attachment to see the contents.

Note that the messaging and computing system described herein may be implemented under a software as a service licensing and delivery model, and customers may license the software for the messaging and computing system on a subscription basis.

Sending Message and/or Content

FIG. 2 presents a flowchart illustrating a method for sending a message and/or content to a recipient in accordance with an embodiment. Note that different embodiments may vary according to detail and order of operations, and embodiments are not limited to the specific operations depicted in the figure. During operation, the sending device can initially receive a message as inputted by the user. The system may also receive content uploaded by the user or selected by the user (operation 202). The system can also receive rules and permissions from the user for the message and/or content (operation 204). The system can also use default rules and permissions for the message and/or content.

The sending device can then encrypt the message and/or content, which may include rules, permissions, a security object that includes permission and rule data, a unique identifier, and/or any other data (operation 206). The sending device can encrypt data using a symmetric key, and then encrypt the symmetric key separately for each intended recipient using a recipient-specific public key. The sending device system sends the encrypted symmetric keys to multiple devices. The recipients of the encrypted symmetric keys can use their own private key to decrypt and extract the symmetric key, and use the symmetric key to decrypt data sent from the sending device.

Generally, the system may encrypt all objects using a per-object symmetric encryption key, and the system encrypts the key for a symmetric key-encrypted object using asymmetric encryption. That is, the sending device need only encrypt an object once using a symmetric key and then encrypt the symmetric key specifically for each recipient. The sending device need not encrypt an object multiple times for different recipients. This saves time and is more efficient because some of the objects may be large file attachments or content (e.g., 1 terabyte or larger).

The system may use a different symmetric key for encrypting each object and does not reuse a symmetric key to encrypt a different object. For example, the system uses a different symmetric key for encrypting each of the message, the message attachment, a thumbnail attachment, and all other objects associated with the message. Thus, even if a malicious party may attack and compromise one symmetric key (e.g., for an attachment), the other symmetric keys remain intact (e.g., for other objects associated with the message).

The system can generate a universally unique identifier for identifying data or portions of the data. For example, the system (e.g., sending device) may split a large file into two portions and generate a unique identifier for the larger portion. The system may send the unique identifier to a receiving device and the server. The unique identifier functions as a key to a distributed hash table. This distributed hash table can be implemented over multiple servers. The distributed hash table stores the association between the stored data and the unique identifier. The receiving device can send a query with the unique identifier to any server that implements the distributed hash table and/or stores a copy of the data. Note that the unique identifier is optionally stored via a distributed lookup table including but not limited to a distributed hash table. The receiving device can retrieve the data from any number of servers since the data may be replicated and stored on multiple servers.

Next, the sending device can send a large encrypted (or unencrypted) portion of the message and/or content of a predetermined size to an enterprise server or a server in the cloud for storage (operation 208). For example, if the message includes a large file attachment, the sending device can encrypt the large file attachment, and split the file (encrypted or unencrypted) into two portions (e.g., the first 100 bytes of the file for small portion and the remainder of the file for the large portion). The sending device can then send the bigger portion of the file attachment to a server that the receiving device can retrieve from. The system may retain the small portion of the data and store it locally within a secure storage of the system, and, in some embodiments, can also include a copy of the small portion when sending a message. Without the small portion of the data, the receiving device (and malicious attackers) may not be able to put together the complete set of data. In some embodiments, the sending device can split the encrypted file (or an unencrypted file) into multiple portions that include more than two portions, and the portions can vary in size. For example, there can be many small pieces, one large and one small, one large and several small, etc. Furthermore, the server may also send the entire encrypted large file attachment or content to a server.

The system may send a large portion of the encrypted (or unencrypted) file to a server that is one of many enterprise hardware devices within an enterprise computing environment, or the server can be part of the messaging and computing system. In some embodiments, the system may also access a server of a cloud service (e.g., Dropbox or Google cloud storage) on the Internet to send and store data.

The sending device may then send the message and/or content, which may include rules, permissions, the unique identifier, the security object, the small portion of the encrypted (or unencrypted) file (or a link to the small portion), and/or any other data to the receiving device (operation 210). In some embodiments, the sending device may send contact information, passwords, lists, and draft messages to other users, encrypted or unencrypted, and may revoke the information at a later time or based on a condition set by the user of the sending device.

If the sending device receives a user command to perform an operation on the message and/or content (operation 212), the sending device may send the command to the receiving device to execute the command (operation 214). In some embodiments, the receiving device can also forward the command to other devices that have been forwarded the message.

In some implementations, the sending device may receive data from a computing device indicating they received a copy of the forwarded message. The sending device may directly send the command to any device that has received a copy of the forwarded message. Devices that receive the command may then comply with the command.

Receiving Message and/or Content

FIG. 3 presents a flowchart illustrating a method for receiving a message and/or content in accordance with an embodiment. Note that different embodiments may vary according to order of operations, and embodiments are not limited to the specific operations depicted in the figure.

A receiving device may initially receive the message and/or content (operation 302). The receiving device may receive the message and/or content from a device that originally sent the message and/or content, or from a device that forwarded the message and/or content. The receiving device may receive the message via a messaging server. The message and/or content may be encrypted (or unencrypted) and the receiving device may decrypt and/or extract various data from the message and/or content received. This data may include one or more of rules, permissions, a universally unique identifier, a link to a substantial portion of an encrypted (or unencrypted) large file attachment or content stored on a remote server, a small portion of the encrypted (or unencrypted) large file attachment or content (e.g., a small .zip file), a security object, and/or any other data included with the message (operation 304). In some embodiments, the receiving device may receive a link to a small portion of a large file attachment or other content, and query a server for the small portion rather than receive the small portion with the message.

The receiving device may obtain additional data from a server if the message and/or content indicates that a portion of a large encrypted (or unencrypted) file is stored elsewhere (operation 306). For example, if the message includes a large file attachment, then the receiving device may retrieve a large encrypted (or unencrypted) portion of the file attachment from a remote server. The receiving device sends the unique identifier to one or more servers over the network and then receives the corresponding data back from a server. The receiving device can retrieve the stored data (e.g., large file attachment or other content) from any one of multiple servers that replicate the additional data. The receiving device may then combine together the split portions of the large file attachment or content. If the receiving device can successfully decrypt an entire encrypted file, then the receiving device has obtained the correct data. For example, if the portions are encrypted, then the full encrypted file is a combination of an encrypted piece and an encrypted remainder. The full encrypted file can then be decrypted using the symmetric key whereas the encrypted piece or encrypted remainder would fail to decrypt independent of each other. The big portion (e.g., remainder file) may be publicly available on Dropbox, a web server, etc. A diff file (e.g., a much smaller portion) may be securely transmitted or stored somewhere. The receiving device may apply the diff file to the remainder file to generate a file equal to the original file (encrypted or not). Note that in some scenarios, a device may combine together portions of an unencrypted file.

Note that multiple servers may implement a distributed hash table storing associations between the universally unique identifier and objects such as file attachments or content. The unique identifier may function as a lookup key for the distributed hash table. The servers can look up the distributed hash table to identify the correct object to return to a device that submits a query using a corresponding unique identifier.

The distributed hash table may also store public keys for users or receiving devices, so that a sending device can request a public key for any potential recipient. The sending device can obtain public keys for multiple recipients, and may send each recipient the same symmetric key but the symmetric key is encrypted using each recipient's specific public key. Each recipient can decrypt and extract the symmetric key using their own specific private key.

Since the stored data is replicated and distributed on different servers, there are multiple ways in which the receiving device can obtain the stored data. In some embodiments, the receiving device can attempt to retrieve the stored data by sending a query with the unique identifier key to a local hardware device or an enterprise computing device. The local hardware device may return the data or may provide the receiving device with information on servers that store the data and their respective download speeds, including which servers provide fastest download speed. The receiving device can attempt to retrieve the stored data by submitting a query to servers with access to the distributed hash table and/or stored copies of the data, and receiving data from a server that is known to be trusted. The receiving device can also retrieve data by sending the query with the unique identifier key to a server that is part of the messaging and communication system (e.g., the software as a service). In some cases it may be faster for the receiving device to access an enterprise hardware device to retrieve data over a local area network but if the receiving device does not have access to the enterprise hardware device, then the receiving device can access the data from the software as a service.

The receiving device may then display the message or otherwise make the content available to the user of the receiving device (operation 308).

If the receiving device receives user input indicating an operation on the message and/or content (operation 310), the receiving device may determine whether the operation is authorized based on the rules and permissions (operation 312). If the operation is authorized, then the receiving device may execute the operation on the message and/or content (operation 314). The receiving device continues to manage the message and/or content while complying with the rules and permissions (operation 316). For example, the receiving device may determine when to delete an object based on a rule associated with the object. As another example, the receiving device may receive subsequent requests to perform operations on the message and/or content and the receiving device may only perform such operations when authorized by the permissions and rules.

Anonymously Accessing External Service

FIG. 4 presents a flowchart illustrating a method for anonymously accessing an external service in accordance with an embodiment. Note that different embodiments may vary according to order of operations, and embodiments are not limited to the specific operations depicted in the figure. Further, some embodiments may execute the process of FIG. 4 entirely on a mobile device, while in other embodiments, a mobile device may use a server to anonymously access external services.

The system may include a zero-login feature that allows a user to add and use an external service, such as a social networking service, without logging in to the external service. The external service can be any service provider, such as Twitter or an SMS text messaging service provider. The system acts as a proxy to allow the user to anonymously access the external services. For example, the user can anonymously use the social networking service to contact (e.g., e-mail or text message) or send data to others until the user wants to authenticate his identity with the social networking service. The system provides the user with an anonymous user ID and the user only needs to indicate the identity of the other party that the user wants to communicate with. The other party sees the message coming from the anonymous user ID. In one embodiment, the receiving party receives a message with a link, and the message informs the receiving party that an anonymous user is trying to communicate with the receiving party or send a file to the receiving party. The receiving party may then click the link to view the message or obtain the file.

In some embodiments, the user can authenticate himself to the system using a login associated with an external service, such as an e-mail address, a Twitter account, or a Facebook account. The system can verify that the user owns the login account on the external service. The system can also verify how other users can message the user via the external service using the login (e.g., e-mail address, SMS number, social user name, etc.). After the user authenticates himself for a particular external service, the system may reveal the true identity of the user on the external service to the recipients of anonymous communications and/or other data from the user. After the user's identity is revealed, the user would directly receive messages and content data from other users on the external service.

During a zero-login process, the system may initially receive a user selection of an external service and user entry of a message and/or content (operation 402). The user may also select content from his local device or on a network. The system may then send the user communication and/or content as an anonymous user to the external service (operation 404). For example, the system may send the message “how are you?” to another user on a social networking service. The other user will receive the message but without any information identifying who was the sender.

The system may then receive user input verifying the user's identity for a particular external service (operation 406). The system may verify the user identity with the external service. The system may then use the verified user identity for the external service (operation 408).

Setting Rules for New Message

FIG. 5 presents an illustration of a screen that allows a user to set rules for a new message in accordance with an embodiment. As illustrated in FIG. 5, a screen 500 displays a new message text entry area 502. The message is addressed to a recipient Lisa. The user can set when the system will delete the message. On the depicted screen the user has adjusted the “delete after” setting 504 so that the system (e.g., a receiving device) will delete the message after a receiving party first views the message. Also, the user can adjust a “delete after a screenshot” switch 506 (e.g., currently enabled) so that the system will delete the message after the receiving device takes a screenshot of the message. The user can also adjust a “notify after a screenshot” switch 508 so that the sending party is notified of any screenshots taken by receiving parties. On the depicted screen, switch 508 is set to a disabled position so the sending party is not notified of screenshots taken by receiving parties. The system includes a setting 510 that allows the user to select whether the rules apply to all recipients or a selection of recipients.

Change Permissions on Recipients of New Message

FIG. 6 presents an illustration of a screen that allows a user to change permissions on all recipients of a new message in accordance with an embodiment. As illustrated in FIG. 6, a screen 600 displays a message text entry area 602. The message is addressed to a recipient Lisa. The user can adjust a forwarding switch 604 (e.g., currently enabled) to allow other users to forward the message, and can adjust a stashing switch 606 (e.g., currently enabled) to allow other users to stash (e.g., archive or move to a folder for storage and/or classification) the message.

A stash is also a location synchronized across all user devices for message drafts, uploaded files, notes, passwords, objects etc. that may be then sent or shared via the platform. The stash may function as a virtual hard drive. Stash allows the user to save versioned objects of all types to the distributed system for later viewing, sharing, collaboration and group editing, and sending. A user can put his items in stash to have it appear on all of the user's other devices. Everything stored with stash may be encrypted. Only the user and the people that the user specifies may view/edit, etc. and have the power to roll back to old versions, view thumbnails (e.g., similar to the attachment view), and search/sort in a manner similar to messages and attachments. Some examples of stash features include but are not limited to message drafts, files, and notes.

Message drafts—these are messages a user started to compose and wishes to resume editing on a different device or pass off to a different user to edit. The message draft may or may not be encrypted, and the sender and any shared viewers/editors may be given various levels of permissions to access the message draft. Multiple versions can be saved and rolled back, and the user can view the differences between versions, etc. Some embodiments can also support files that have been uploaded to the system and attached but not sent.

Files—this is a very safe and secure file hosting service. A user can upload one-to-many files and folders, assign permissions on who can view/access/edit, assign tags to classify a file, and set reminders to perform some action on the file. Some embodiments may also support all versioning features, roll back viewable differences, etc.

Notes—includes, but is not limited to, free form text, pictures, video, Global Positioning System (GPS) location, maps, voice, etc. with note-taking capability. Users can tag, attach files, assign permissions, set reminders, and use versioning capability.

The user can also adjust a switch 608 to allow other users to add participants (e.g., currently disabled), and can adjust a “removing participants” switch 610 (e.g., currently enabled) to allow other users to remove participants. Note that the user can also change permissions for a single recipient or any set of recipients. Other examples of permissions include but are not limited to printing, selecting text, and external downloading.

Hierarchical Display of Group Messages

FIG. 7 presents an illustration of a screen that shows an exemplary hierarchical display of group messages in accordance with an embodiment. The system may also include a hierarchical structure and hierarchical display for group messaging. The system manages and stores group messaging data using a hierarchical structure. This hierarchical display utilizes a tree structure to illustrate the threads of a conversation when multiple users are communicating with each other. The user may then easily follow the threads of the group conversation and see who is responding to whom in the conversation. Existing group messaging software typically only displays a scrolling interface that displays each message as a user sends out the message. It is difficult for a user to follow the different threads of a group conversation with existing group messaging software.

As illustrated in FIG. 7, a screen 700 displays a group messaging session between users Rey, Henry, and Brian. The three users are represented in the users panel display 702. The messages in the group messaging session can be organized in a hierarchical display. This hierarchical display resembles a tree structure that allows the user to easily follow the conversation threads, since replies to a message are displayed as nested within (e.g., branching off from) the message.

A picture or other user icon (e.g., pictures 704 a, 704 b, 704 c, 704 d) depicting each user and a corresponding message may be indented within screen area 706 to show responses to Henry's question. For example, the user can more easily follow the responses to Henry's question (e.g., “Chipotle?”) since the responses in screen area 706 are indented to show that the responses are nested within the original question. In some implementations, the screen area 706 may be shaded with light grey highlight or some other shading or color to indicate responses to Henry's question. A message input box 708 allows a user to input a question to send to participants in the messaging group (e.g., “How about wings?”).

In some implementations, a user may click on a reply message in a conversation thread to cause the system to display the original message that the reply message is directed at. For example, a user may click on a message display box 710 displaying “Sounds good” and then the system will pop-up and display the original message that started the thread (e.g., “Chipotle?”). The system may display the pop-up visual indicator indicating the content and sender for the message “Chipotle?” that started the thread. The system may also respond to the user clicking on the pop-up visual indicator by navigating to the original message “Chipotle?” and graying out the reply messages in the thread. This makes it easier to navigate business-oriented threads with a large number of messages. Some embodiments may also display a fork in a thread when a user forwards a message.

FIG. 8 illustrates an exemplary computer system that facilitates a messaging and content sharing platform with sender-controlled security in accordance with an embodiment. In this example, a system 800 for messaging and content sharing can include but is not limited to a processor 802, a memory device 804, and a storage device 806. System 800 may optionally include a display module 808, an input module 810, and a communication module 812. In some embodiments, system 800 may be implemented on a mobile device, and in other embodiments, one or more components of system 800 may also be implemented on another computing device, such as a server.

Storage device 806 can store instructions which when loaded into memory 804 and executed by processor 802 cause processor 802 to perform the aforementioned operations (e.g., for a sending device or a receiving device). More specifically, the instructions stored in storage device 806 can include an encryption/decryption module 814, a security module 816, and an identity management module 818.

Encryption/decryption module 814 encrypts and decrypts objects such as messages, attachments, and other content objects. Security module 816 manages the rules and permissions associated with objects. Identity management module 818 verifies the identity of the user. It can verify the identity of the user with external services such Twitter, e-mail, and Facebook. Identity management module 818 can also act as a proxy for the user when the user seeks to use external services anonymously. In some embodiments, identity management module 818 may be implemented on a server, and a mobile device may interact with a server executing identity management module 818 to access external services anonymously.

The data structures and code described in this detailed description are typically stored on a computer-readable storage medium, which may be any device or medium that can store code and/or data for use by a computer system. The computer-readable storage medium includes, but is not limited to, volatile memory, non-volatile memory, magnetic and optical storage devices such as disk drives, magnetic tape, CDs (compact discs), DVDs (digital versatile discs or digital video discs), or other media capable of storing computer-readable media now known or later developed.

The methods and processes described in the detailed description section can be embodied as code and/or data, which can be stored in a computer-readable storage medium as described above. When a computer system reads and executes the code and/or data stored on the computer-readable storage medium, the computer system performs the methods and processes embodied as data structures and code and stored within the computer-readable storage medium.

Furthermore, the methods and processes described above can be included in hardware modules. For example, the hardware modules can include, but are not limited to, application-specific integrated circuit (ASIC) chips, field-programmable gate arrays (FPGAs), and other programmable-logic devices now known or later developed. When the hardware modules are activated, the hardware modules perform the methods and processes included within the hardware modules.

The foregoing descriptions of embodiments of the present invention have been presented for purposes of illustration and description only. They are not intended to be exhaustive or to limit the present invention to the forms disclosed. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. Additionally, the above disclosure is not intended to limit the present invention. The scope of the present invention is defined by the appended claims. 

1. A method for sending an object comprising: receiving the object at a sending device, wherein the object is a message or other content; receiving user input at the sending device to set permissions and rules for the object, wherein a respective permission indicates a respective operation that a receiving device may perform on the object, and wherein a respective rule indicates an operation that the receiving device is required to perform when a specified condition occurs in connection with the object; attaching the permissions and rules to the object; and sending, by the sending device, at least a portion of the object to the receiving device.
 2. The method of claim 1, further comprising: generating a unique identifier for a portion of the object; sending the portion of the object with the unique identifier to a server, wherein the unique identifier is optionally stored via a distributed lookup table including but not limited to a distributed hash table; sending the unique identifier to the receiving device.
 3. The method of claim 1, further comprising in a messaging session involving a plurality of users displaying responses to each user according to a hierarchical structure so that a response to a message in a message thread is depicted as branching off from the message.
 4. The method of claim 1, wherein a rule is one of: disallowing the receiving device from forwarding the message; disallowing the receiving device from taking a screenshot of the object; disallowing the receiving device from printing the object; disallowing the receiving device from downloading the object; requiring that the receiving device delete an object after taking a screenshot; and requiring that the receiving device delete an object after the user views the object.
 5. The method of claim 1, further comprising: allowing the user to anonymously send a message and/or other content to an external service; verifying the identity of the user; and allowing the user to receive messages from others and continue messaging with others using the user's verified identity.
 6. The method of claim 1, further comprising: displaying a plurality of messages in attachment view so that the user may view only the attachments, wherein an attachment includes a generated thumbnail for each file that is smaller than the original size of the file.
 7. The method of claim 1, wherein a permission indicates whether the receiving device is allowed to perform one of the following: forward the message and/or content; stash the message and/or content; add a participant to a message header indicating parties that receive the message and associated replies; remove a participant from the message header indicating parties that receive the message and associated replies; take a screenshot that includes the message and/or content select text from the message and/or content; print the message and/or content; and download the message and/or content to external storage.
 8. The method of claim 1, wherein the object is encrypted with a symmetric key and the symmetric key is encrypted with a public key of the receiving device; and wherein sending the portion of the object further comprises: encrypting the object and sending a portion of the encrypted object to the receiving device.
 9. The method of claim 1, further comprising receiving user input to specify permissions for others to access and roll back an item in a stash.
 10. The method of claim 1, further comprising: performing optical character recognition on attachments; receiving user input specifying a search item, and searching through the attachments and associated metadata for the search item.
 11. A method performed by a receiving device to receive an object comprising: receiving the object at the receiving device, wherein the object is a message or other content; extracting permissions and rules from the object, wherein the permission and rules are set at a sending device according to user input received at the sending device, wherein a respective permission indicates a respective operation that the receiving device may perform on the object, and wherein a respective rule indicates an operation that the receiving device is required to perform when a specified condition occurs in connection with the object; and providing the object to a user.
 12. The method of claim 11, wherein the object is encrypted, and wherein decrypting the object involves obtaining an encrypted portion of the object from a server.
 13. The method of claim 11, further comprising: receiving user input specifying an operation to be performed on the object; determining whether the operation is authorized based on the rules and/or permissions of the object; and responsive to determining that the operation is authorized, performing the operation on the object.
 14. The method of claim 12, wherein the object is encrypted and extracting permissions further comprises: decrypting and extracting a symmetric key from the message using a private key of the receiving device; and decrypting the object with the symmetric key.
 15. A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for sending an object, the method comprising: receiving the object at a sending device, wherein the object is a message or other content; receiving user input at the sending device to set permissions and rules for the object, wherein a respective permission indicates a respective operation that a receiving device may perform on the object, and wherein a respective rule indicates an operation that the receiving device is required to perform when a specified condition occurs in connection with the object; attaching the permissions and rules to the object; and sending, by the sending device, at least a portion of the object to the receiving device.
 16. The storage medium of claim 15, wherein the method further comprises: generating a unique identifier for a portion of the object; sending the portion of the object with the unique identifier to a server, wherein the unique identifier is optionally stored via a distributed lookup table including but not limited to a distributed hash table; sending the unique identifier to the receiving device.
 17. The storage medium of claim 15, wherein the method further comprises: in a messaging session involving a plurality of users displaying responses to each user according to a hierarchical structure so that a response to a message in a message thread is depicted as branching off from the message.
 18. The storage medium of claim 15, wherein a rule is one of: disallowing the receiving device from forwarding the message; disallowing the receiving device from taking a screenshot of the object; disallowing the receiving device from printing the object; disallowing the receiving device from downloading the object; requiring that the receiving device delete an object after taking a screenshot; and requiring that the receiving device delete an object after the user views the object.
 19. The storage medium of claim 15, wherein the method further comprises: allowing the user to anonymously send a message and/or other content to an external service; verifying the identity of the user; and allowing the user to receive messages from others and continue messaging with others using the user's verified identity.
 20. The storage medium of claim 15, wherein a permission indicates whether the receiving device is allowed to perform one of the following: forward the message and/or content; stash the message and/or content; add a participant to a message header indicating parties that receive the message and associated replies; remove a participant from the message header indicating parties that receive the message and associated replies; take a screenshot that includes the message and/or content select text from the message and/or content; print the message and/or content; and download the message and/or content to external storage.
 21. A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method executed by a receiving device to receive an encrypted object, the method comprising: receiving the object at the receiving device, wherein the object is a message or other content; extracting permissions and rules from the object, wherein the permissions and rules are set at a sending device according to user input received at the sending device, wherein a respective permission indicates a respective operation that the receiving device may perform on the object, and wherein a respective rule indicates an operation that the receiving device is required to perform when a specified condition occurs in connection with the object; and providing the object to a user.
 22. The storage medium of claim 21, wherein the object is encrypted, and wherein decrypting the object involves obtaining an encrypted portion of the object from a server
 23. The storage medium of claim 21, wherein the method further comprises: receiving user input specifying an operation to be performed on the object; determining whether the operation is authorized based on the rules and/or permissions of the object; and responsive to determining that the operation is authorized, performing the operation on the object.
 24. A system comprising: a processor; a memory; and a non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for sending an object, the method comprising: receiving the object at a sending device, wherein the object is a message or other content; receiving user input at the sending device to set permissions and rules for the object, wherein a respective permission indicates a respective operation that a receiving device may perform on the object, and wherein a respective rule indicates an operation that the receiving device is required to perform when a specified condition occurs in connection with the object; attaching the permissions and rules to the object; sending, by the sending device, at least a portion of the object to the receiving device.
 25. The system of claim 24, wherein the method further comprises: generating a unique identifier for a portion of the object; sending the portion of the object with the unique identifier to a server, wherein the unique identifier is optionally stored via a distributed lookup table including but not limited to a distributed hash table; sending the unique identifier to the receiving device.
 26. The system of claim 24, wherein the method further comprises: allowing the user to anonymously send a message and/or other content to an external service; verifying the identity of the user; and allowing the user to receive messages from others and continue messaging with others using the user's verified identity.
 27. A system comprising: a processor; a memory; and a non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for receiving an object, the method comprising: receiving the object at a receiving device, wherein the object is a message or other content; extracting permissions and rules from the object, wherein the permissions and rules are set at a sending device according to user input received at the sending device, wherein a respective permission indicates a respective operation that the receiving device may perform on the object, and wherein a respective rule indicates an operation that the receiving device is required to perform when a specified condition occurs in connection with the object; and providing the object to a user.
 28. The system of claim 27, wherein the method further comprises: receiving user input specifying an operation to be performed on the object; determining whether the operation is authorized based on the rules and/or permissions of the object; and responsive to determining that the operation is authorized, performing the operation on the object.
 29. The system of claim 27, wherein the object is encrypted, and wherein decrypting the object involves obtaining an encrypted portion of the object from a server 